Answer:
2.1 rad/s
Step-by-step explanation:
Given that,
Mass of a tether ball, m = 0.546 kg
Length of a rope, l = 4.56 m
The maximum tension the rope can withstand before breaking is 11.0 N
We need to find the maximum angular speed of the ball. Let v is the linear velocity. The maximum tension is balanced by the centripetal force acting on it. It can be given by :

Let
is the angular speed of the ball. The relation between the angular speed and angular velocity is given by :

So, the maximum angular speed of the ball is 2.1 rad/s.